Campylodiscus sp., single example on the slide. Mounted in Sirax and dated May 1941. Prepared by Samuel Henry Meakin. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 151 images stacked in Zerene (Pmax). I would have like to have used the 63x Leitz Pl Apo objective, however I couldn’t get close enough with it, presumably due to the angle the diatom is at. This was a big stack due to its orientation.
Although a species name is not given, the slide label refers Schmidt’s Atlas, Plate 208, Figure 8. A translation from this gives: “Sumbawa (Kinker), cf. 14.45. According to Cleve, C. decorus Breb. typ. Grove would like to classify this form as C. biangulatus Grev.”. Looking at the pictures it could be this, but I am not 100% sure.